Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2018

Fair Value Measurements [Abstract]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

	September 30, 2018
(in thousands)	Level 1		Level 2		Level 3		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	89,312	$	—	$	89,312
Municipal obligations		—		232,713		—		232,713
Corporate debt securities		—		3,500		—		3,500
Residential mortgage-backed securities		—		1,731,275		—		1,731,275
Commercial mortgage-backed securities		—		722,882		—		722,882
Collateralized mortgage obligations		—		138,503		—		138,503
Total available for sale securities		—		2,918,185		—		2,918,185
Derivative assets (1)		—		11,411		—		11,411
Total recurring fair value measurements - assets	$	—	$	2,929,596	$	—	$	2,929,596
Liabilities
Derivative liabilities (1)	$	—	$	28,791	$	—	$	28,791
Total recurring fair value measurements - liabilities	$	—	$	28,791	$	—	$	28,791

	December 31, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Assets
Available for sale debt securities:
U.S. Treasury and government agency securities	$	—	$	97,272	$	—	$	97,272
Municipal obligations		—		243,786		—		243,786
Corporate debt securities		—		3,500		—		3,500
Residential mortgage-backed securities		—		1,715,213		—		1,715,213
Commercial mortgage-backed securities		—		687,135		—		687,135
Collateralized mortgage obligations		—		163,963		—		163,963
Total available for sale securities		—		2,910,869		—		2,910,869
Derivative assets (1)		—		14,157		—		14,157
Total recurring fair value measurements - assets	$	—	$	2,925,026	$	—	$	2,925,026
Liabilities
Derivative liabilities (1)	$	—	$	14,389	$	—	$	14,389
Total recurring fair value measurements - liabilities	$	—	$	14,389	$	—	$	14,389

(1) For further disaggregation of derivative assets and liabilities, see Note 6 - Derivatives.

Financial Assets Measured at Fair Value on Nonrecurring Basis

	September 30, 2018
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	180,730	$	—	$	180,730
Other real estate owned and foreclosed assets, net		—		—		24,900		24,900
Total nonrecurring fair value measurements	$	—	$	180,730	$	24,900	$	205,630

	December 31, 2017
(in thousands)	Level 1		Level 2		Level 3		Total
Collateral-dependent impaired loans	$	—	$	184,205	$	—	$	184,205
Other real estate owned and foreclosed assets, net		—		—		19,595		19,595
Total nonrecurring fair value measurements	$	—	$	184,205	$	19,595	$	203,800

Estimated Fair Values of Financial Instruments

	September 30, 2018
							Total Fair		Carrying
(in thousands)	Level 1		Level 2		Level 3		Value		Amount
Financial assets:
Cash, interest-bearing bank deposits, and federal funds sold	$	447,683	$	—	$	—	$	447,683	$	447,683
Available for sale securities		—		2,918,185		—		2,918,185		2,918,185
Held to maturity securities		—		2,975,455		—		2,975,455		3,069,262
Loans, net		—		180,730		18,843,738		19,024,468		19,329,167
Loans held for sale		—		29,043		—		29,043		29,043
Derivative financial instruments		—		11,411		—		11,411		11,411
Financial liabilities:
Deposits	$	—	$	—	$	22,373,052	$	22,373,052	$	22,417,807
Federal funds purchased		50,325		—		—		50,325		50,325
Securities sold under  agreements to repurchase		415,960		—		—		415,960		415,960
FHLB short-term borrowings		1,810,362		—		—		1,810,362		1,810,362
Long-term debt		—		213,076		—		213,076		215,912
Derivative financial instruments		—		28,791		—		28,791		28,791

	December 31, 2017
							Total Fair		Carrying
(in thousands)	Level 1		Level 2		Level 3		Value		Amount
Financial assets:
Cash, interest-bearing bank deposits, and federal funds sold	$	479,332	$	—	$	—	$	479,332	$	479,332
Available for sale securities		—		2,910,869		—		2,910,869		2,910,869
Held to maturity securities		—		2,962,010		—		2,962,010		2,977,511
Loans, net		—		184,205		18,403,303		18,587,508		18,786,855
Loans held for sale		—		39,865		—		39,865		39,865
Derivative financial instruments		—		14,157		—		14,157		14,157
Financial liabilities:
Deposits	$	—	$	—	$	22,238,847	$	22,238,847	$	22,253,202
Federal funds purchased		140,754		—		—		140,754		140,754
Securities sold under  agreements to repurchase		430,569		—		—		430,569		430,569
FHLB short-term borrowings		1,132,567		—		—		1,132,567		1,132,567
Long-term debt		—		303,631		—		303,631		305,513
Derivative financial instruments		—		14,389		—		14,389		14,389